Welcome back. Apple just made their biggest bet on AI. They dropped iOS 27 with a ton of new updates for everyone out there. Meanwhile, the AI vs. humanity debate shows no signs of slowing down as Chinese researchers jump into the ring. Let's dive in.
Also: A viral Trump-Jensen Huang phone call where the president had a lot to say about AI, development, could video games actually be good for your brain, and why Gen Z seems to be redefining what “senior” even means in engineering.
Today’s Brief
Build a custom agent harness
Meta engineer on the reality of the AI race
How to upgrade your Pi agents (tutorial)
Google’s guide to pairing Claude + Gemini (cookbook)

TODAY IN PROGRAMMING
Apple pitches the iPhone as an AI playground for devs: The iPhone maker just rolled out iOS 27 with an upgraded Foundation Models framework. This framework lets you plug in any language model with a single Swift API. You can choose from Apple’s own on- device models to cloud models like Claude and Gemini. Siri is getting more agentic too, with App Intents letting it reach into apps and take actions for users, and its also getting it’s own app for the first time.
You can now customise Claude Code with Mods: Anthropic is rolling out “Claude Mods,” a new plugin system that lets developers tweak how Claude Code looks and behaves with simple TypeScript functions. Mods can hide sensitive info during screen shares, track token usage, or even run games above the prompt. For teams, admins can also disable risky capabilities across the entire org, something older tools couldn’t reliably enforce. You can try Mods behind an env flag. This was followed by a statement from Anthropic’s Addy Osmani claiming that Claude now writes 80% of their production code, helping the team ship eight times more.
China joins the debate over where AI is heading: The AI vs. humanity debate sparked by an Anthropic researcher’s resignation last week has a new voice. A DeepSeek engineer says the bigger danger is not runaway AI but one company controlling AGI. He argues for open, cheap frontier models and even compares Anthropic getting AGI first to Hitler getting the bomb. OpenAI's Dan Selsam also chimed in with a different concern. He warns that powerful models, or swarms of them, could develop unintended goals that humans can no longer control.

PRESENTED BY WISPR
Not because you don't care. Because after 6 hours of building, typing paragraphs about what you built feels like punishment.
So the PR description stays vague. The README gets "TODO." The architecture decision lives in your head until you leave the company.
Wispr Flow: syntax-aware voice dictation that works in every app. Speak your PR descriptions, commit messages, and docs. camelCase, snake_case, and acronyms stay intact.
Engineers at OpenAI and Vercel use it daily. Available on Mac, Windows, iPhone, and Android. The best docs are the ones that actually get written.

INSIGHT
You need to build a custom agent harness now

Source: The Code, Superhuman
Hot Topic. Yesterday, we broke down why AI startups are going all in on domain-specific agent harnesses. YC CEO Garry Tan says nearly every software startup at the latest Demo Day is building one, while OpenAI, LangChain, and Anthropic keep making them easier to create.
So today, we’re doing the obvious next thing which is actually building one.
The starting point. LangChain product manager Sydney Runkle starts with create_agent, LangChain’s basic building block for wiring a model into an agent loop with tools and instructions. From there, she puts it simply: an agent is just a model plus a harness, and making that harness genuinely useful comes down to three moves:
Start bare. Plug a model into create_agent, hand it a few tools, and add a prompt. It handles the core loop automatically which is to pick a tool, check the output, figure out the next step, and repeat until it finishes the job.
Add middleware. This handles everything that a prompt can't do. It trims context before it gets out of hand, retries failed tools, redacts sensitive data, pauses for human review, and caps your spend. Most common pieces are already built out, so you only need to plug in what's unique to your setup.
Fit the task. Tailor the harness to the exact job instead of squeezing everything into one generic wrapper. For example, a support agent needs a totally different setup than a coding agent. It all boils down to one single idea: a great agent starts with a harness that feeds the model exactly what it needs for the job.
Code your leverage. A capable model only gives you a starting line today and not a competitive advantage. Teams build their real leverage through the harness by tailoring custom tools, context, guardrails, and workflows to a specific task. You can build one end to end (apparently in minutes) with LangChain's Quickstart.

IN THE KNOW
What’s trending on socials and headlines

Meme of the day.
Viral callback: Trump dialed Nvidia CEO Jensen Huang live onstage at the All-In Summit, and his take on AI regulation instantly lit up the internet (1.9M views).
Title Trouble: An ex-Snap engineer spotted a pattern across tech companies that is redefining what "senior" even means, and peers say she nailed it (259K views).
Gamer Brains: A study on how gaming shapes your brain is blowing up the internet, and Elon Musk put it bluntly, "Play video games or be dumb!" (5.9M views).
Claude Code for Founders: A founder just turned his bestselling book into code. The Minimalist Entrepreneur now runs as 9 Claude Code skills that guide you through building a startup step by step (7.6K bookmarks).
OpenAI CTO on Astra: OpenAI set Astra loose on its own systems to hunt vulnerabilities. CTO Greg Brockman says the results were a lesson for the entire team (727K views).

TOP & TRENDING RESOURCES
Top Tutorial
How to code with Pi coding agent: This tutorial shows how to turn Pi from a minimal agent harness into something much more capable. You’ll learn how to add subagents for parallel work and MCP for connecting external tools, so you can build more complex agentic workflows without moving to a heavier framework.
Top Repo
Open Code Review (23.2k ⭐): Alibaba’s AI code review tool reads your Git diffs, pulls in wider repo context, and leaves precise line-level comments instead of generic feedback. It combines hard-coded review steps with an LLM agent, which Alibaba says helps it use about 1/9 the tokens of general-purpose agents like Claude Code.
Trending Cookbook
Putting Claude and Gemini on the same agent team (by Google): Google Cloud shows why you shouldn’t force one model to do everything. The guide uses Gemini 3.8 Flash as the fast, cheap worker for routine tasks, then escalates harder or irreversible work to Claude Fable 5.1 for deeper planning. It also walks through benchmarking both models on your own tasks and wiring them into the same agent workflow.

AI CODING HACK
How to stop subagents from draining your Fable 5.1 usage
Fable 5.1 spawns subagents constantly, and each one runs on your session model by default. Most subagent tasks don't need Fable-level reasoning. Developer Lydia Hallie shared a one-line fix that routes them to Opus instead.
Step 1: Set the environment variable before launching Claude Code:
export CLAUDE_CODE_SUBAGENT_MODEL=opusStep 2: To make it permanent, add it to
.claude/settings.json:
{
"env": {
"CLAUDE_CODE_SUBAGENT_MODEL": "opus"
}
}Step 3: Restart Claude Code. Your main conversation stays on Fable 5.1. Subagents now run on Opus and stop eating your usage.
One caveat: this sets the default for subagents without a pinned model. Full model resolution order is in the subagent docs.
P.S. Get 50+ AI coding hacks for Claude Code, Cursor, and Codex here.

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Until next time — The Code team




